Bentgrass is not a grass or turf species that is desirable in home lawns. This winter has been hard on a lot of bentgrass patches in lawns.
Here is one where a patch of bentgrass has turned brown. If Georgina (her lawn in the picture) is lucky, the bentgrass will have died and it can be replaced with a more desirable mix of turfgrasses. Knowing, however, that Murphy’s law is usually at work in these circumstances, it is most likely that the damaged bentgrass will perk up in a few weeks and be as green and healthy as ever. While bentgrass is easily affected by winterkill and will be brown and dead-looking in the early spring, it rarely completely dies out. It’s just the upper foliage that has turned brown. Once the weather and the soil warm up, it will recover and be ready to spread out and overrun other parts of the lawn.
If your lawn is showing a great deal of bentgrass that has been: "winter-killed", you may want to take this opportunity to give it a hard raking to get rid of the dead stems and to thin out the unwanted bentgrass. Then add some soil and a high quality grass seed mix. This will thin out the bentgrass for a while. Be forewarned, however, that there will likely be enough bentgrass left so that in a few years it will be back as thick and strong as ever.
More on bentgrass in the library